The presence of an online on PC will make the community online more cohesive than the actual separation between PS and Xbox, without counting the fact that should be much better to create an improved netcode or also a better online experience. The pros of all the orthodox and unorthodox possibilities seems to me overcome the cons.
You can add specific settings for hard LAN results. Connectivity and lag are very minor compared to consoles. Besides, aren't they are going to stop nude mods?